1. Technical Field
The present disclosure relates to an instrument for spinal surgery and, more particularly, to surgical instruments and methods for forming a keel channel in vertebral bodies.
2. Discussion of Related Art
Surgical procedures are performed to correct problems with displaced, damaged, or degenerated intervertebral discs due to trauma, disease, or aging. One of the most common procedures is spinal fusion. However, total disc replacement procedures are being utilized as an alternative to spinal fusion. The replacement procedure involves implantation of devices designed to replace the functions of the intervertebral disc and thus preserve motion that is lost through a spinal fusion.
The implant generally has an implant body and a keel structure, which can augment anti-migration features of the implant and further stabilize the position of the implant within the intervertebral space. Keel structures may extend above the upper surface and/or below the lower surface. Keel structures may be canted or generally perpendicular to the surface from which they extend. During implantation the keel structures can be inserted into keel channels formed in the adjacent vertebrae. Apertures may be provided along the length of the keel, or a portion thereof, to permit bony ingrowth through the keel structures.
Current surgical procedures utilize a trial sizer instrument and a separate keel cutter. The trial sizer may be inserted into the intervertebral space to determine the size of an appropriate implant required to achieve the desired disc height. The keel cutter is then advanced into the intervertebral space to form channels in the vertebral bodies for receiving the keel structures that are present on the implant.
Therefore, a continuing need exists for an improved device and a method for determining a desired implant size and forming a keel channel that can minimize the number of instruments, steps, and time involved in a surgical procedure.